JP2010060478A

JP2010060478A - Position detection device of linear/rotary motor and linear/rotary motor

Info

Publication number: JP2010060478A
Application number: JP2008227792A
Authority: JP
Inventors: Yasushi Yoshida; 吉田　　康; Toru Shikayama; 透鹿山; Masanobu Kakihara; 正伸柿原
Original assignee: Yaskawa Electric Corp
Current assignee: Yaskawa Electric Corp
Priority date: 2008-09-05
Filing date: 2008-09-05
Publication date: 2010-03-18
Anticipated expiration: 2028-09-05
Also published as: JP5200778B2

Abstract

【課題】回転方向に対して、絶対角度を検出できる直動回転モータの位置検出装置を提供する。
【解決手段】位置置検出装置は直動変位検出部、回転変位検出部、直動方向に一定間隔に設けた直動目盛を有する円筒状の直動スケール、円筒状で、前記直動方向に対して垂直方向に２極着磁された永久磁石で構成される。回転変位検出部は出力軸の回転中心に対して異なる回転角に複数の磁界検出素子を設けている。出力軸の回転による永久磁石の発生磁界は、出力軸１回転につき１周期の正弦波状の変化を示す。この磁界の変化を複数の磁界検出素子で検出して、信号処理することにより、出力軸の絶対角度を検出する。
【選択図】図１A position detection device for a linear motion rotary motor capable of detecting an absolute angle with respect to a rotation direction is provided.
A position detector includes a linear motion displacement detector, a rotational displacement detector, a cylindrical linear motion scale having linear motion graduations provided at regular intervals in the linear motion direction, and a cylindrical shape in the linear motion direction. On the other hand, it is composed of a permanent magnet that is two-pole magnetized in the vertical direction. The rotational displacement detection unit is provided with a plurality of magnetic field detection elements at different rotation angles with respect to the rotation center of the output shaft. The magnetic field generated by the permanent magnet due to the rotation of the output shaft shows a sinusoidal change of one cycle per one rotation of the output shaft. The change of the magnetic field is detected by a plurality of magnetic field detection elements, and signal processing is performed to detect the absolute angle of the output shaft.
[Selection] Figure 1

Description

本発明は、直動回転モータの出力軸の位置を検出する直動回転モータの位置検出装置およびそれを用いた直動回転モータに関する。
The present invention relates to a position detection device for a direct acting rotation motor that detects the position of an output shaft of the direct acting rotation motor, and a direct acting rotation motor using the position detecting device.

１つのアクチュエータで、回転と直動の２つの動作をおこなう直動回転モータが開示されている（例えば、特許文献１参照）。
この中で、出力軸の直動変位と回転変位を検出する装置として、図９の検出部が示されている。１７は回転目盛、７は直動目盛である。回転目盛１７と空隙を介して対向して回転検出器６が配置され、直動目盛７と対向して直動検出器５が配置された構成となっている。回転目盛１７と直動目盛７は直列に配置されており、それに合わせて回転検出部６と直動検出部５も配置されている。回転目盛１７と直動目盛７は、エッチングなどで製作された微小間隔の凹凸の光学的な目盛で構成されており、その目盛は全周にわたって施されている。一方、回転検出部６と直動検出部５には、レーザ光を照射し、凹凸の目盛を介して反射されたレーザ光を検知して、回転位置θと直動位置Ｚを読み取る光学式検出手段を備えている。ここで、回転目盛７および直動目盛１７が取り付けられた出力軸が回転および直動すると、回転検出部６と直動検出部５によって、回転位置θと直動位置Ｚを得ることができる。 A linear motion rotary motor that performs two operations of rotation and linear motion with one actuator is disclosed (for example, see Patent Document 1).
Among these, the detector of FIG. 9 is shown as a device for detecting the linear displacement and the rotational displacement of the output shaft. Reference numeral 17 is a rotary scale, and 7 is a linear scale. The rotation detector 6 is arranged to face the rotary scale 17 with a gap, and the linear motion detector 5 is arranged to face the linear motion scale 7. The rotation scale 17 and the linear motion scale 7 are arranged in series, and the rotation detection unit 6 and the linear motion detection unit 5 are also arranged in accordance therewith. The rotary scale 17 and the linear motion scale 7 are constituted by optical scales with minute intervals formed by etching or the like, and the scales are provided over the entire circumference. On the other hand, the rotation detection unit 6 and the linear motion detection unit 5 are irradiated with laser light, detected by the laser beam reflected through the uneven scale, and optical detection for reading the rotational position θ and the linear motion position Z. Means. Here, when the output shaft to which the rotary scale 7 and the linear motion scale 17 are attached rotates and linearly moves, the rotational position θ and the linear motion position Z can be obtained by the rotation detector 6 and the linear motion detector 5.

また、図１０は、回転目盛７と直動目盛１７を磁気的な目盛で構成したものである。
特開２００７−１４３３８５号公報 FIG. 10 shows a rotary scale 7 and a linear scale 17 that are magnetic scales.
JP 2007-143385 A

回転位置について注目すれば、従来の直動回転モータの回転位置検出装置は、等間隔に刻まれた回転目盛を使用している。したがって、原点基準位置がないため、任意の点を基準にした相対的は変位量しか検出できず、原点基準位置に対する相対的な回転位置すら検出出来ないという問題点があった。
そのため、直動回転モータのシステムとして、回転基準位置に対する相対的な位置決め動作が必要な場合、外部原点センサを付加すれば可能となるが、そうした場合も
原点復帰動作が必要であり、始動に時間がかかるなどの問題があった。
本発明はこのような問題点に鑑みてなされたものであり、直動回転モータの絶対的な回転位置が検出できる位置検出装置を提供することを目的とする。
If attention is paid to the rotational position, the conventional rotational position detecting device for the linear motion rotary motor uses rotational scales that are engraved at equal intervals. Accordingly, since there is no origin reference position, there is a problem that only a displacement amount can be detected relative to an arbitrary point, and even a rotational position relative to the origin reference position cannot be detected.
For this reason, if a positioning operation relative to the rotation reference position is required as a linear motion rotation motor system, it can be achieved by adding an external origin sensor. There was a problem such as taking.
The present invention has been made in view of such problems, and an object of the present invention is to provide a position detection device capable of detecting the absolute rotational position of a linear motion rotary motor.

上記問題を解決するため、本発明は、次のように構成したものである。
請求項１に記載の発明は、回転方向および直動方向に移動する出力軸を有するモータ部の前記出力軸の回転位置および直動位置を検出する直動回転モータの位置検出装置において、前記位置検出装置は、直動方向に一定間隔に設けた直動目盛を有する円筒状の直動スケールと、円筒状で前記直動方向に対して垂直方向に、２極着磁された永久磁石と、前記直動スケールから直動方向の変位を検出する直動変位検出部と、前記永久磁石の磁界から回転方向の変位を検出する回転変位検出部を備えたことを特徴としている。 In order to solve the above problems, the present invention is configured as follows.
The invention according to claim 1 is a position detection device for a linear motion rotary motor that detects a rotational position and a linear motion position of the output shaft of a motor unit having an output shaft that moves in a rotational direction and a linear motion direction. The detection apparatus includes a cylindrical linear motion scale having linear graduations provided at regular intervals in the linear motion direction, a permanent magnet that is cylindrical and perpendicularly polarized with respect to the linear motion direction, and A linear motion displacement detector that detects a displacement in the linear motion direction from the linear motion scale, and a rotational displacement detector that detects a displacement in the rotational direction from the magnetic field of the permanent magnet are provided.

請求項２に記載の発明は、回転方向および直動方向に移動する出力軸を有するモータ部の前記出力軸の回転位置および直動位置を検出する直動回転モータの位置検出装置において、前記位置検出装置は、直動方向に一定間隔に設けた直動目盛を有する円筒状の直動スケールと、円板状で、前記直動方向に対して垂直方向に２極着磁された複数の永久磁石と、前記直動スケールから直動方向の変位を検出する直動変位検出部と、前記永久磁石の磁界から回転方向の変位を検出する回転変位検出部を備えたことを特徴としている。 According to a second aspect of the present invention, there is provided a position detecting device for a linear motion rotary motor that detects a rotational position and a linear motion position of the output shaft of a motor unit having an output shaft that moves in a rotational direction and a linear motion direction. The detection device includes a cylindrical linear motion scale having linear motion graduations provided at regular intervals in the linear motion direction, and a plurality of permanent magnets that are disk-shaped and are two-pole magnetized in a direction perpendicular to the linear motion direction. It is characterized by comprising a magnet, a linear displacement detector that detects displacement in the linear motion direction from the linear motion scale, and a rotational displacement detector that detects displacement in the rotational direction from the magnetic field of the permanent magnet.

請求項３に記載の発明は、回転方向および直動方向に移動する出力軸を有するモータ部と、前記出力軸の回転位置および直動位置を検出する直動回転モータの位置検出装置において、前記位置検出装置は、直動方向に一定間隔に設けた直動目盛を有する円筒状の直動スケールと、円板状で、前記直動方向に対して垂直方向に２極着磁された永久磁石と、前記直動スケールから直動方向の変位を検出する直動変位検出部と、直動方向の異なる位置に前記永久磁石の磁界から回転方向の変位を検出する複数の回転変位検出部を備えたことを特徴としている。 According to a third aspect of the present invention, there is provided a motor unit having an output shaft that moves in a rotational direction and a linear motion direction, and a position detection device for a linear motion rotary motor that detects a rotational position and a linear motion position of the output shaft. The position detection device includes a cylindrical linear motion scale having linear graduations provided at regular intervals in the linear motion direction, and a disk-shaped permanent magnet magnetized in two directions perpendicular to the linear motion direction. A linear displacement detector that detects displacement in the linear motion direction from the linear motion scale, and a plurality of rotational displacement detectors that detect displacement in the rotational direction from the magnetic field of the permanent magnet at different positions in the linear motion direction. It is characterized by that.

請求項４に記載の発明は請求項２記載の直動回転モータの位置検出装置において前記出力軸が特定の複数ケ所の直動位置に移動したとき、前記複数の永久磁石のいずれかが前記回転変位検出部に近接するように複数の永久磁石が配置されていることを特徴としている。
請求項５に記載の発明は請求項２記載の直動回転モータの位置検出装置において前記複数の磁石は２個であって、出力軸が特定の２カ所の直動位置に移動したとき、第１の永久磁石または第２の永久磁石が、回転変位検出部に近接するように取り付けていることを特徴としている。 According to a fourth aspect of the present invention, in the position detecting device for a linear motion rotary motor according to the second aspect, when the output shaft moves to a plurality of specific linear motion positions, any of the plurality of permanent magnets is rotated. A plurality of permanent magnets are arranged so as to be close to the displacement detector.
According to a fifth aspect of the present invention, in the position detecting device for a linear motion rotary motor according to the second aspect, when the plurality of magnets are two and the output shaft moves to two specific linear motion positions, 1 permanent magnet or 2nd permanent magnet is attached so that it may adjoin to a rotation displacement detection part.

請求項６に記載の発明は請求項３記載の直動回転モータの位置検出装置において前記出力軸が特定の複数ケ所の直動位置に移動したとき、前記永久磁石が前記複数の回転変位検出部のいずれかに近接するように前記回転変位検出部を設けていることを特徴としている。
請求項７に記載の発明は請求項３記載の直動回転モータの位置検出装置において前記複数の回転変位検出部は２個であって、前記出力軸が特定の２カ所の直動位置に移動したときに前記回転変位検出部のいずれかが前記永久磁石に近接するように取り付けられていることを特徴としている。 According to a sixth aspect of the present invention, in the linear motion rotary motor position detection device according to the third aspect, when the output shaft moves to a plurality of specific linear motion positions, the permanent magnet is moved to the plurality of rotational displacement detectors. The rotational displacement detector is provided so as to be close to any of the above.
According to a seventh aspect of the present invention, in the linear motion rotary motor position detection device according to the third aspect of the present invention, the plurality of rotational displacement detectors are two, and the output shaft moves to two specific linear motion positions. In this case, one of the rotational displacement detectors is attached so as to be close to the permanent magnet.

請求項８に記載の発明は請求項１から３のいずれか１項記載の直動回転モータの位置検出装置において前記直動スケールは光学式スケールであり、前記直動変位検出部は反射型リニアエンコーダであることを特徴としている。
請求項９に記載の発明は請求項１から３のいずれか１項記載の直動回転モータの位置検出装置において前記直動スケールは磁気式スケールであり、前記直動変位検出部は磁気式センサであることを特徴としている。
請求項１０に記載の発明は請求項１から３のいずれか１項記載の直動回転モータの位置検出装置において前記直動スケールは凹凸の形状もしくは滑らかな山谷形状を設けた軟磁性材料より形成するとともに、前記直動変位検出部はインダクタンス変化を検出する手段であることを特徴としている。
請求項１１に記載の発明は請求項１から３のいずれか１項記載の直動回転モータの位置検出装置において前記回転変位検出部は前記出力軸の回転中心に対して複数の異なる回転角に磁界検出素子を設けたことを特徴としている。
請求項１２に記載の発明は請求項１１記載の直動回転モータの位置検出装置において前記磁界検出素子は前記出力軸回転中心に対して９０度異なる回転角にホール素子または磁気抵抗素子をおのおの設けたことを特徴としている。
請求項１３に記載の発明における直動回転モータが請求項１から３のいずれか１項記載の直動回転モータの位置検出装置を備えたことを特徴としている。
According to an eighth aspect of the present invention, in the position detecting device for a linear motion rotary motor according to any one of the first to third aspects, the linear motion scale is an optical scale, and the linear motion displacement detector is a reflective linear type. It is an encoder.
According to a ninth aspect of the present invention, in the linear motion rotary motor position detection device according to any one of the first to third aspects, the linear motion scale is a magnetic scale, and the linear displacement detector is a magnetic sensor. It is characterized by being.
According to a tenth aspect of the present invention, in the position detecting device for a linear motion rotary motor according to any one of the first to third aspects, the linear motion scale is formed of a soft magnetic material having an uneven shape or a smooth mountain valley shape. In addition, the linear displacement detector is a means for detecting an inductance change.
According to an eleventh aspect of the present invention, in the linear motion rotary motor position detection device according to any one of the first to third aspects, the rotational displacement detector is set at a plurality of different rotation angles with respect to the rotation center of the output shaft. A magnetic field detecting element is provided.
According to a twelfth aspect of the present invention, in the position detecting device for a linear motion rotary motor according to the eleventh aspect, each of the magnetic field detecting elements is provided with a Hall element or a magnetoresistive element at a rotation angle different by 90 degrees with respect to the output shaft rotation center. It is characterized by that.
According to a thirteenth aspect of the present invention, there is provided a linear motion rotary motor comprising the linear motion rotary motor position detecting device according to any one of the first to third aspects.

請求項１記載の発明によると、円筒状で底面に対して水平方向に一方向に磁化された永久磁石の発生磁界を検出するので、出力軸の絶対的な回転位置の検出ができる。
請求項２，４，５の発明によると、回転位置を検出したい特定の直動位置に円板状の磁石を配置するので、使用する磁石の体積を小さくでき、低コストで出力軸の特定の直動位置の絶対的な回転位置が検出できる。
請求項３，６，７の発明によると、円板状の磁石を１つだけ使用するので、使用する磁石の体積をより小さくでき、低コストで出力軸の特定の直動位置の絶対的な回転位置が検出できる。 According to the first aspect of the present invention, since the magnetic field generated by the permanent magnet that is cylindrical and magnetized in one direction horizontally with respect to the bottom surface is detected, the absolute rotational position of the output shaft can be detected.
According to the second, fourth, and fifth aspects of the present invention, since the disk-shaped magnet is arranged at the specific linear motion position where the rotational position is to be detected, the volume of the magnet to be used can be reduced, and the specific output shaft can be specified at low cost. The absolute rotational position of the linear motion position can be detected.
According to the third, sixth, and seventh aspects of the invention, since only one disk-shaped magnet is used, the volume of the magnet to be used can be further reduced, and the absolute position of the specific linear motion position of the output shaft can be reduced at a low cost. The rotational position can be detected.

請求項８の発明によると、直動位置を精密に刻まれた光学スケールを用い、光学式検出手段で検出するため正確な直動位置を検出することができる。
請求項９，１０の発明によると、直動回転位置の検出手段が磁気式、レゾルバ式であるので周囲温度が高い用途でも使用することができる。
請求項１１，１２の発明によると、絶対的な回転位置を演算により容易に演算できるとともに回転方向の検出ができる。
請求項１３の発明によると、絶対的な回転位置に位置決め可能な直動回転モータが得られる。
According to the eighth aspect of the present invention, an accurate linear motion position can be detected because an optical scale in which the linear motion position is precisely carved is detected by the optical detection means.
According to the ninth and tenth aspects of the invention, the linear motion rotational position detecting means is a magnetic type or a resolver type, so that it can be used even in applications where the ambient temperature is high.
According to the inventions of claims 11 and 12, the absolute rotation position can be easily calculated by calculation and the rotation direction can be detected.
According to the thirteenth aspect of the present invention, a linear motion rotary motor that can be positioned at an absolute rotational position is obtained.

以下、本発明の実施の形態について図を参照して説明する。 Hereinafter, embodiments of the present invention will be described with reference to the drawings.

図１は、本発明の第１実施例を示す直動回転モータの側断面図である。
図１において、直動回転モータはモータ部１と位置検出装置２から構成される。モータ部１では、出力軸３が回転方向および直動方向に移動できるように、回転・直動軸受４に支持されている。
位置検出装置２は、直動変位検出部５、回転変位検出部６、直動方向に一定間隔に設けた直動目盛を有する円筒状の直動スケール7、円筒状で前記直動方向に対して垂直方向に２極着磁された永久磁石８で構成されている。
前記直動スケール７は円筒状の部材の全周に目盛を形成した光学式スケールである。研磨した金属表面に直接目盛りを形成してもよいし、部材表面に製膜したクロム膜等の反射率の高い薄膜金属に目盛りを形成してもよい。、
８は円筒状の磁石であり、図２のように中実の形状であってもかまわないし、図３のように他の材料からなるシャフト９に固定された中空の形状であってもかまわない。
直動変位検出部５はＬＥＤや半導体レーザからなる光源、固定スリット、フォトダイオード等の受光素子からなり、直動スケール７と組み合わせて、反射型リニアエンコーダの構成を取り、出力軸３が直動するとその直動方向の変位を検出できる。ただし、直動スケール７には全周にわたって目盛が形成されているので、出力軸３が任意の回転角に回転しても直動方向の位置を検出できる。
回転変位検出部６は出力軸３の回転中心に対して異なる回転角に複数の磁界検出素子を設けている。図４は、磁界検出素子として２つのホール素子１０ａと１０ｂを用いた場合の図１のＡ−Ａ線断面図である。 FIG. 1 is a side sectional view of a linear motion rotary motor showing a first embodiment of the present invention.
In FIG. 1, the linear motion rotary motor includes a motor unit 1 and a position detection device 2. In the motor unit 1, the output shaft 3 is supported by the rotary / linear motion bearing 4 so that the output shaft 3 can move in the rotational direction and the linear motion direction.
The position detection device 2 includes a linear motion displacement detector 5, a rotational displacement detector 6, a cylindrical linear motion scale 7 having a linear motion scale provided at regular intervals in the linear motion direction, and a cylindrical shape with respect to the linear motion direction. And a permanent magnet 8 that is two-pole magnetized in the vertical direction.
The linear motion scale 7 is an optical scale having a scale formed on the entire circumference of a cylindrical member. A scale may be directly formed on the polished metal surface, or a scale may be formed on a thin film metal having a high reflectance such as a chromium film formed on the surface of the member. ,
Reference numeral 8 denotes a cylindrical magnet, which may be a solid shape as shown in FIG. 2 or a hollow shape fixed to a shaft 9 made of another material as shown in FIG. .
The linear displacement detector 5 is composed of a light source composed of an LED or a semiconductor laser, a light receiving element such as a fixed slit, a photodiode, etc., and is combined with the linear motion scale 7 to form a reflective linear encoder, and the output shaft 3 is linearly moved. Then, the displacement in the linear motion direction can be detected. However, since the scale is formed over the entire circumference of the linear motion scale 7, the position in the linear motion direction can be detected even if the output shaft 3 rotates to an arbitrary rotation angle.
The rotational displacement detection unit 6 is provided with a plurality of magnetic field detection elements at different rotation angles with respect to the rotation center of the output shaft 3. FIG. 4 is a cross-sectional view taken along line AA of FIG. 1 when two Hall elements 10a and 10b are used as the magnetic field detection elements.

次に、出力軸３の回転位置を検出する原理について説明する。
回転変位検出部の第１のホール素子１０ａは、永久磁石８から発生する半径方向の磁界を検出する。ここで、出力軸３の直動位置Ｚを固定し、回転位置θを変化させると、ホール素子１０ａが検出する磁界の大きさは、回転位置θの大きさに応じて、出力軸３の１回転につき１周期の正弦波状に変化する。これによりホール素子１０ａの出力電圧Ｖ１も回転位置θに関して正弦波となる。出力軸９の回転中心に対して、第１のホール素子１０ａと９０度異なる位置に配置した第２のホール素子１０ｂも同様に磁界の変化を検出し、出力電圧Ｖ２は、回転位置θに関してＶ1と90度位相が異なる正弦波となる。
従って、出力軸３の回転位置θは第１、第２のホール素子の出力電圧Ｖ１とＶ２を用いて、
θ＝ｔａｎ^−１（Ｖ１／Ｖ２）［ｒａｄ］
で計算することができる。
得られた回転位置θは、出力軸３の絶対的な回転位置を示すものであり、常に絶対的な回転位置を検出することができる。

本実施例の直動回転モータの位置検出装置を備えた直動回転モータは、外部原点センサを用いず、絶対的な位置決めが可能である。また、絶対位置が検出されるので、外部厳選センサを用いたときに必要となる原点復帰動作が不要であり、始動時間が短縮される。
Next, the principle of detecting the rotational position of the output shaft 3 will be described.
The first Hall element 10 a of the rotational displacement detection unit detects a radial magnetic field generated from the permanent magnet 8. Here, when the linear motion position Z of the output shaft 3 is fixed and the rotational position θ is changed, the magnitude of the magnetic field detected by the Hall element 10a is 1 of the output shaft 3 according to the magnitude of the rotational position θ. It changes into a sine wave shape of one cycle per rotation. As a result, the output voltage V1 of the Hall element 10a also becomes a sine wave with respect to the rotational position θ. The second Hall element 10b arranged at a position 90 degrees different from the first Hall element 10a with respect to the rotation center of the output shaft 9 similarly detects a change in the magnetic field, and the output voltage V2 is V1 with respect to the rotational position θ. And a 90-degree phase sine wave.
Therefore, the rotational position θ of the output shaft 3 is determined by using the output voltages V1 and V2 of the first and second Hall elements,
θ = tan ⁻¹ (V1 / V2) [rad]
Can be calculated with
The obtained rotational position θ indicates the absolute rotational position of the output shaft 3, and the absolute rotational position can always be detected.

The direct acting rotation motor provided with the position detecting device of the direct acting rotation motor of the present embodiment can be absolutely positioned without using an external origin sensor. In addition, since the absolute position is detected, the origin return operation required when using the external carefully selected sensor is unnecessary, and the starting time is shortened.

図５は、本発明の第２実施例を示す直動回転モータの側断面図である。
図５において、第１の実施例と異なる点は、円筒状の永久磁石の代わりに、直動方向の異なる位置に円板状の永久磁石を２つ配置した点である。８ａは第１の永久磁石、８ｂは第２の永久磁石である。第１の永久磁石８a、第２の永久磁石８ｂとも、中実の形状であってもかまわないし、他の材料からなるシャフトに固定された中空の形状であってもかまわない。また、図６に示すように、出力軸３が特定の２カ所の直動位置Ｚ１（図６のＡの状態）またはＺ２（図６のＢの状態）に移動したとき、第１の永久磁石８ａまたは第２の永久磁石８ｂが、回転変位検出部６に近接するように取り付けている。
この構成の直動回転モータは直動位置が２点間の往復運動をし、上記のようにＺ１とＺ２の位置でのみ回転位置が計測できれば良い用途などに適し、実施例１の構成に対して永久磁石を円筒状から２枚の円板状にすることにより永久磁石の軽量化が図れる。 FIG. 5 is a sectional side view of a linear motion rotary motor showing a second embodiment of the present invention.
In FIG. 5, the difference from the first embodiment is that two disk-like permanent magnets are arranged at different positions in the linear motion direction instead of the cylindrical permanent magnet. 8a is a first permanent magnet, and 8b is a second permanent magnet. Both the first permanent magnet 8a and the second permanent magnet 8b may have a solid shape, or may have a hollow shape fixed to a shaft made of another material. Further, as shown in FIG. 6, when the output shaft 3 moves to two specific linear motion positions Z1 (state A in FIG. 6) or Z2 (state B in FIG. 6), the first permanent magnet 8 a or the second permanent magnet 8 b is attached so as to be close to the rotational displacement detector 6.
The linear motion rotary motor of this configuration is suitable for applications where the linear motion position reciprocates between two points and the rotational position can be measured only at the positions of Z1 and Z2, as described above. The weight of the permanent magnet can be reduced by changing the shape of the permanent magnet from a cylindrical shape to two discs.

次に、出力軸３の回転位置を検出する原理について説明する。
まず、出力軸３が直動位置Ｚ１にあるとき、第２の永久磁石８ｂが回転変位検出部６に近接しているので、回転変位検出部６のホール素子は、出力軸３の回転位置θに応じた第２の永久磁石８ｂの磁界変化を検出する。
実施例１同様、回転変位検出部６の互いに９０度異なる位置に配置された第１のホール素子１０ａと、第２のホール素子１０ｂが検出する磁界の大きさは、回転位置θの大きさに応じてそれぞれ正弦波状に変化し、かつその位相は９０度異なる。
従って、出力軸３の回転位置θ１は第１のホール素子１０ａ、第２のホール素子１０ｂの出力電圧Ｖ１とＶ２を用いて、
θ１＝ｔａｎ^−１（Ｖ１／Ｖ２）［ｒａｄ］
で計算することができる。 Next, the principle of detecting the rotational position of the output shaft 3 will be described.
First, when the output shaft 3 is in the linear motion position Z1, the second permanent magnet 8b is close to the rotational displacement detector 6, so that the Hall element of the rotational displacement detector 6 is connected to the rotational position θ of the output shaft 3. The magnetic field change of the second permanent magnet 8b according to the above is detected.
As in the first embodiment, the magnitudes of the magnetic fields detected by the first hall element 10a and the second hall element 10b arranged at positions 90 degrees different from each other in the rotational displacement detector 6 are set to the magnitude of the rotational position θ. In response to this, each changes in a sinusoidal shape, and the phase is different by 90 degrees.
Accordingly, the rotational position θ1 of the output shaft 3 is obtained by using the output voltages V1 and V2 of the first Hall element 10a and the second Hall element 10b.
θ1 = tan ⁻¹ (V1 / V2) [rad]
Can be calculated with

つぎに、出力軸３が直動位置Ｚ２にあるとき、第１の永久磁石８ａが回転変位検出部６の磁気検出素子に近接している。回転変位検出部６は、出力軸３の回転位置θに応じた第１の永久磁石８ａの磁界変化を検出する。
従って、出力軸３の回転位置θ２は実施例１同様の回転変位検出部６の第１のホール素子１０ａ、第２のホール素子１０ｂの出力電圧Ｖ１とＶ２を用いて、
θ２＝ｔａｎ^−１（Ｖ１／Ｖ２）［ｒａｄ］
で計算することができる。 Next, when the output shaft 3 is in the linear motion position Z2, the first permanent magnet 8a is close to the magnetic detection element of the rotational displacement detector 6. The rotational displacement detector 6 detects a change in the magnetic field of the first permanent magnet 8 a according to the rotational position θ of the output shaft 3.
Therefore, the rotational position θ2 of the output shaft 3 is obtained by using the output voltages V1 and V2 of the first Hall element 10a and the second Hall element 10b of the rotational displacement detector 6 similar to the first embodiment,
θ2 = tan ⁻¹ (V1 / V2) [rad]
Can be calculated with

出力軸３が直動位置Ｚ１にあるときの出力軸３の回転位置θ１および、出力軸３が直動位置Ｚ２にあるときの出力軸３の回転位置θ２は、第１の永久磁石８aと第２の永久磁石８ｂの回転方向の取り付け精度により異なることも考えられるが、θ１、θ２はそれぞれ絶対的な回転位置を検出するため、常にその差は等しく、必要に応じて図示しない後段の信号処理回路で、あらかじめ差の値を記憶していれば、補正可能である。
また、出力軸３が直動位置Ｚ１と直動位置Ｚ２の間にあるときには、回転方向の位置の検出ができないが、直動位置Ｚ１または直動位置Ｚ２にまで移動が完了すれば、再び回転位置θ１または回転位置θ２が検出できる。これは、本実施例で得られる回転位置θ１および回転位置θ２それぞれが絶対的な回転位置だからである。

本実施例の直動回転モータの位置検出装置を備えた直動回転モータは、外部原点センサを用いず、絶対的な位置決めが可能である。また、絶対位置が検出されるので、外部厳選センサを用いたときに必要となる原点復帰動作が不要であり、始動時間が短縮される。
The rotational position θ1 of the output shaft 3 when the output shaft 3 is in the linear motion position Z1 and the rotational position θ2 of the output shaft 3 when the output shaft 3 is in the linear motion position Z2 are the first permanent magnet 8a and the It is conceivable that the two permanent magnets 8b may differ depending on the mounting accuracy in the rotational direction. However, since θ1 and θ2 each detect the absolute rotational position, the difference between them is always the same. If the difference value is stored in advance in the circuit, it can be corrected.
Further, when the output shaft 3 is between the linear motion position Z1 and the linear motion position Z2, the position in the rotational direction cannot be detected, but when the movement to the linear motion position Z1 or the linear motion position Z2 is completed, the rotation is resumed. The position θ1 or the rotational position θ2 can be detected. This is because each of the rotational position θ1 and the rotational position θ2 obtained in this embodiment is an absolute rotational position.

The direct acting rotation motor provided with the position detecting device of the direct acting rotation motor of the present embodiment can be absolutely positioned without using an external origin sensor. In addition, since the absolute position is detected, the origin return operation required when using the external carefully selected sensor is unnecessary, and the starting time is shortened.

図７は、本発明の第３実施例を示す直動回転モータの側断面図である。
図７において、第１の実施例と異なる点は、円筒状の永久磁石の代わりに、円板状の永久磁石を用いるとともに、回転変位検出部を直動方向の異なる２カ所に配置した点である。
８ｄは永久磁石であり、中実の形状であってもかまわないし、他のシャフト部材に固定された中空の形状であってもかまわない。また、図８に示すように、出力軸３が特定の２カ所の直動位置Ｚ１（図８のＡの状態）またはＺ２（図８のＢの状態）に移動したとき、永久磁石８ｄが近接するように、それぞれ第１の回転変位検出部６ａと第２の回転変位検出部６ｂを設けている。 FIG. 7 is a side sectional view of a linear motion rotary motor showing a third embodiment of the present invention.
In FIG. 7, the difference from the first embodiment is that a disk-shaped permanent magnet is used instead of a cylindrical permanent magnet, and the rotational displacement detectors are arranged at two places with different linear motion directions. is there.
Reference numeral 8d denotes a permanent magnet, which may be a solid shape or a hollow shape fixed to another shaft member. Further, as shown in FIG. 8, when the output shaft 3 moves to two specific linear motion positions Z1 (state A in FIG. 8) or Z2 (state B in FIG. 8), the permanent magnet 8d approaches. As shown, a first rotational displacement detector 6a and a second rotational displacement detector 6b are provided.

次に、出力軸３の回転位置を検出する原理について説明する。
まず、出力軸３が直動位置Ｚ１にあるとき、永久磁石８ｄが第１の回転変位検出部６ａに近接しているので、第１の回転変位検出部６ａが、出力軸３の回転位置θに応じた永久磁石８ｄの磁界変化を検出する。
実施例１同様、第１の回転変位検出部６ａの互いに９０度異なる位置に配置された第１のホール素子１０ａと、第２のホール素子１０ｂが検出する磁界の大きさは、回転位置θの大きさに応じてそれぞれ正弦波状に変化し、なおかつその位相は９０度異なる。
従って、出力軸３の回転位置θ１は第１の回転変位検出部内の第１のホール素子１０ａ、第２のホール素子１０ｂの出力電圧Ｖ１とＶ２を用いて、
θ１＝ｔａｎ^−１（Ｖ１／Ｖ２）［ｒａｄ］
で計算することができる。 Next, the principle of detecting the rotational position of the output shaft 3 will be described.
First, when the output shaft 3 is in the linear motion position Z1, since the permanent magnet 8d is close to the first rotational displacement detector 6a, the first rotational displacement detector 6a is connected to the rotational position θ of the output shaft 3. A change in the magnetic field of the permanent magnet 8d corresponding to is detected.
As in the first embodiment, the magnitudes of the magnetic fields detected by the first Hall element 10a and the second Hall element 10b arranged at positions 90 degrees different from each other in the first rotational displacement detector 6a are the rotational positions θ. It changes in a sine wave shape according to the size, and the phase differs by 90 degrees.
Therefore, the rotational position θ1 of the output shaft 3 is obtained by using the output voltages V1 and V2 of the first Hall element 10a and the second Hall element 10b in the first rotational displacement detector.
^{θ1 = tan -1 (V1 / V2} ) [rad]
Can be calculated with

つぎに、出力軸３が直動位置Ｚ２にあるとき、永久磁石８ｄが第２の回転変位検出部６ｂに近接しているので、第２の回転変位検出部６ｂが、出力軸３の回転位置θに応じた永久磁石８ｄの磁界変化を検出する。
実施例１同様、第２の回転変位検出部６ｂの互いに９０度異なる位置に配置された第３のホール素子と１０ａ、第４のホール素子１０ｂが検出する磁界の大きさも、回転位置θの大きさに応じてそれぞれ正弦波状に変化し、なおかつその位相は９０度異なる。
従って、出力軸３の回転位置θ２は第２の回転変位検出部内の第３のホール素子１０ａ、第４のホール素子１０ｂの出力電圧Ｖ３とＶ４を用いて、
θ２＝ｔａｎ^−１（Ｖ３／Ｖ４）［ｒａｄ］
で計算することができる。 Next, when the output shaft 3 is at the linear motion position Z2, the permanent magnet 8d is close to the second rotational displacement detector 6b, so that the second rotational displacement detector 6b is rotated at the rotational position of the output shaft 3. A change in the magnetic field of the permanent magnet 8d corresponding to θ is detected.
As in the first embodiment, the magnitude of the magnetic field detected by the third Hall element 10a and the fourth Hall element 10b, which are arranged at 90 ° different positions of the second rotational displacement detector 6b, is also the magnitude of the rotational position θ. Each of them changes in a sine wave shape, and the phase differs by 90 degrees.
Accordingly, the rotational position θ2 of the output shaft 3 is obtained by using the output voltages V3 and V4 of the third Hall element 10a and the fourth Hall element 10b in the second rotational displacement detector.
θ2 = tan ⁻¹ (V3 / V4) [rad]
Can be calculated with

出力軸３が直動位置Ｚ１にあるときの出力軸３の回転位置θ１および、出力軸３が直動位置Ｚ２にあるときの出力軸３の回転位置θ２は、第１の回転変位検出部６ａと第２の回転変位検出部６ｂの回転方向の取り付け精度により異なることも考えられるが、θ１、θ２はそれぞれ絶対的な回転位置を検出するため、常にその差は等しく、必要に応じて図示しない後段の信号処理回路で、あらかじめ差の値を記憶していれば、補正可能である。
また、出力軸３が直動位置Ｚ１と直動位置Ｚ２の間にあるときには、回転方向の位置の検出ができないが、直動位置Ｚ１または直動位置Ｚ２にまで移動が完了すれば、再び回転位置θ１または回転位置θ２が検出できる。これは、本実施例で得られる回転位置θ１および回転位置θ２それぞれが絶対的な回転位置だからである。

本実施例の直動回転モータの位置検出装置を備えた直動回転モータは、外部原点センサを用いず、絶対的な位置決めが可能である。また、絶対位置が検出されるので、外部厳選センサを用いたときに必要となる原点復帰動作が不要であり、始動時間が短縮される。

The rotational position θ1 of the output shaft 3 when the output shaft 3 is at the linear motion position Z1 and the rotational position θ2 of the output shaft 3 when the output shaft 3 is at the linear motion position Z2 are the first rotational displacement detector 6a. May differ depending on the mounting accuracy in the rotational direction of the second rotational displacement detector 6b, but θ1 and θ2 always detect the absolute rotational position, so the difference between them is always the same and is not shown if necessary. Correction is possible if the difference value is stored in advance in the signal processing circuit at the subsequent stage.
Further, when the output shaft 3 is between the linear motion position Z1 and the linear motion position Z2, the position in the rotational direction cannot be detected, but when the movement to the linear motion position Z1 or the linear motion position Z2 is completed, the rotation is resumed. The position θ1 or the rotational position θ2 can be detected. This is because each of the rotational position θ1 and the rotational position θ2 obtained in this embodiment is an absolute rotational position.

The direct acting rotation motor provided with the position detecting device of the direct acting rotation motor of the present embodiment can be absolutely positioned without using an external origin sensor. In addition, since the absolute position is detected, the origin return operation required when using the external carefully selected sensor is unnecessary, and the starting time is shortened.

上記説明ではＺ１，Ｚ２の２点の位置での検出用として説明をしたが、２点に限定されることなく、２点以上の複数の直動位置での直動回転モータの位置検出にも適用可能である。また、本発明では位置検出素子として、ホール素子を用いたが、磁気抵抗効果素子等の他の磁気検出素子を用いても良い。
また、直動スケールとして上記説明では光学式スケール、直動変位検出部として反射型リニアエンコーダで説明したが、直動スケールとして一定間隔でＮ−Ｓ着磁された磁気スケールで、直動変位検出部として磁気式センサ、または直動スケールとして凹凸の形状もしくは滑らかな山谷形状を設けた軟磁性材料より形成されたスケールであり、前記直動変位検出部がインダクタンス変化を検出する手段で有っても良い。
In the above description, the detection is made for detection at the two points Z1 and Z2. However, the detection is not limited to two points, but the detection of the position of the direct-acting rotary motor at two or more linear movement positions is also possible. Applicable. In the present invention, the Hall element is used as the position detection element, but other magnetic detection elements such as a magnetoresistive element may be used.
In the above description, the optical scale is used as the linear motion scale, and the reflective linear encoder is used as the linear motion displacement detection unit. However, the linear motion scale is detected by a magnetic scale magnetized NS at regular intervals as the linear motion scale. A magnetic sensor as a part, or a scale formed from a soft magnetic material having a concave-convex shape or a smooth peak-and-valve shape as a linear motion scale, and the linear motion displacement detection unit is a means for detecting an inductance change Also good.

第１実施例を示す直動回転モータの側断面図Side sectional view of a linear motion rotary motor showing a first embodiment. 第１実施例の永久磁石の１例の斜視図The perspective view of one example of the permanent magnet of 1st Example 第１実施例の永久磁石の他の例の斜視図The perspective view of the other example of the permanent magnet of 1st Example 図１のＡ−Ａ線に沿った断面図Sectional drawing along the AA line of FIG. 第２実施例を示す直動回転モータの側断面図Side sectional view of a linear motion rotary motor showing a second embodiment. 第２実施例の動作を示す直動回転モータの側断面図Side sectional view of a linear motion rotary motor showing the operation of the second embodiment. 第３実施例を示す直動回転モータの側断面図Side sectional view of a linear motion rotary motor showing a third embodiment. 第３実施例の動作を示す直動回転モータの側断面図Side sectional view of a linear motion rotary motor showing the operation of the third embodiment. 従来の直動回転モータの位置検出装置の構造を示す側断面図Side sectional view showing the structure of a position detecting device for a conventional linear motor 従来の直動回転モータの位置検出装置の構造を示す側断面図Side sectional view showing the structure of a position detecting device for a conventional linear motor

Explanation of symbols

１モータ部
２位置検出装置
３出力軸
４回転・直動軸受
５直動変位検出部
６回転変位検出部
６ａ第１の回転変位検出部
６ｂ第２の回転変位検出部
７直動スケール
８、８ｄ永久磁石
８ａ第１の永久磁石
８ｂ第２の永久磁石
９シャフト
１０ａ第１のホール素子
１０ｂ第２のホール素子
１１磁化方向
１７直動目盛 DESCRIPTION OF SYMBOLS 1 Motor part 2 Position detection apparatus 3 Output shaft 4 Rotation / linear motion bearing 5 Linear motion displacement detection part 6 Rotational displacement detection part 6a 1st rotational displacement detection part 6b 2nd rotational displacement detection part 7 Linear motion scale 8, 8d Permanent magnet 8a First permanent magnet 8b Second permanent magnet 9 Shaft 10a First Hall element 10b Second Hall element 11 Magnetization direction 17 Linear motion scale

Claims

In a position detecting device for a linear motion rotary motor that detects a rotational position and a linear motion position of the output shaft of a motor unit having an output shaft that moves in a rotational direction and a linear motion direction,
The position detection device includes a cylindrical linear motion scale having linear motion graduations provided at regular intervals in the linear motion direction, and a permanent magnet magnetized in two poles in a direction perpendicular to the linear motion direction. A linear motion comprising a magnet, a linear displacement detector that detects a displacement in the linear motion direction from the linear motion scale, and a rotational displacement detector that detects a displacement in the rotational direction from the magnetic field of the permanent magnet. Rotation motor position detection device.

In a position detecting device for a linear motion rotary motor that detects a rotational position and a linear motion position of the output shaft of a motor unit having an output shaft that moves in a rotational direction and a linear motion direction,
The position detecting device is a cylindrical linear motion scale having linear motion graduations provided at regular intervals in the linear motion direction, and has a disc shape and is magnetized in two poles in a direction perpendicular to the linear motion direction. A plurality of permanent magnets, a linear displacement detector that detects displacement in the linear motion direction from the linear motion scale, and a rotational displacement detector that detects displacement in the rotational direction from the magnetic field of the permanent magnet, A position detection device for a linear motion rotary motor.

In a position detecting device for a linear motion rotary motor that detects a rotational position and a linear motion position of the output shaft of a motor unit having an output shaft that moves in a rotational direction and a linear motion direction,
The position detecting device is a cylindrical linear motion scale having linear motion graduations provided at regular intervals in the linear motion direction, and has a disc shape and is magnetized in two poles in a direction perpendicular to the linear motion direction. A permanent magnet, a linear displacement detector that detects displacement in the linear motion direction from the linear motion scale, and a plurality of rotational displacement detectors that detect rotational displacement from the magnetic field of the permanent magnet at different positions in the linear motion direction A position detecting device for a direct acting rotation motor, comprising:

A plurality of permanent magnets are arranged so that any one of the plurality of permanent magnets is close to the rotational displacement detector when the output shaft moves to a plurality of specific linear motion positions. The position detection device for a linear motion rotary motor according to claim 2.

The plurality of magnets are two, and the first permanent magnet or the second permanent magnet is attached so as to be close to the rotational displacement detector when the output shaft moves to two specific linear motion positions. The position detecting device for a linear motion rotary motor according to claim 2.

The rotational displacement detector is provided so that the permanent magnet is close to one of the plurality of rotational displacement detectors when the output shaft moves to a specific plurality of linear motion positions. The position detection device for a linear motion rotary motor according to claim 3.

The plurality of rotational displacement detectors are two, and are attached so that one of the rotational displacement detectors comes close to the permanent magnet when the output shaft moves to two specific linear motion positions. The position detecting device for a linear motion rotary motor according to claim 3.

4. The position detection device for a linear motion rotary motor according to claim 1, wherein the linear motion scale is an optical scale, and the linear motion displacement detector is a reflective linear encoder. 5.

4. The position detecting device for a linear motion rotary motor according to claim 1, wherein the linear motion scale is a magnetic scale, and the linear motion displacement detector is a magnetic sensor. 5.

4. The linear motion scale is formed of a soft magnetic material provided with an uneven shape or a smooth mountain-valley shape, and the linear motion displacement detector is a means for detecting an inductance change. The position detection device for a linear motion rotary motor according to any one of the preceding claims.

The position of the direct acting rotation motor according to any one of claims 1 to 3, wherein the rotational displacement detection unit is provided with a magnetic field detection element at a plurality of different rotation angles with respect to the rotation center of the output shaft. Detection device.

12. The position detecting device of a linear motion rotary motor according to claim 11, wherein each of the magnetic field detecting elements is provided with a hall element or a magnetoresistive element at a rotation angle different from the output shaft rotation center by 90 degrees.

A linear motion rotary motor comprising the position detection device for a linear motion rotary motor according to any one of claims 1 to 3.